The Indo-US collaborative research group, at the Byramjee Jeejeebhoy Medical College (BJMC) in Pune, India, is currently conducting the only NIH-sponsored;Phase III randomized clinical trial for prevention of mother-to-child HIV transmission (MTCT) in India. In response to this RFA, we propose a Clinical Trials Unit (CTU) with a single Clinical Research Site (CRS) that will build upon the success of our existing leadership, organization, clinical trials management procedures, as well as our experienced investigators and staff. Our CTU proposes to participate in trials that will address two research priority areas: 1) Prevention of MTCT and 2) Optimization of Clinical Management of HIV-infected Children. Johns Hopkins University (JHU) will be the primary grantee and will support the CTU leadership, administration, community activities and a single CRS in Pune, through two subcontracts (BJMC and ED SEARCH). BJMC will provide scientific and administrative leadership to the CTU, as well as clinical/laboratory infrastructure and clinical care support for the CRS. BJMC will also utilize the help of the National AIDS Research Institute for specialized laboratory support. ED SEARCH, a registered, Indian, non-profit Trust will provide scientific and administrative leadership, as well as day-to-day management of the CRS, regulatory requirements and good clinical practices. ED SEARCH will also manage support of our Community Advisory Board, as well as our trial recruitment program in 21 community-based clinics run by the Pune Municipal Corporation and the Pimpri Chinchwad Municipal Corporation. Our application reflects a fully-functional, experienced, actively-enrolling CTU that has more than three years of experience conducting the only Phase III HIV prevention clinical trial in India. We also have significant infrastructure, a proven GCP track record, and documented capacity for enrollment and retention of mothers and infants. Since August 2003, our CRS has provided HIV voluntary counseling and testing to more than 54,000 pregnant women in Pune. We have enrolled 593 HIV-infected mothers (20/month) in our current MTCT trial. Our capacity for pediatric treatment trials is supported by our active follow-up of 160 HIV-infected children and a supportive community-based referral program. The trajectory and impact of the global HIV epidemic is shifting to Asia and to India. Therefore, our CTU in Pune is uniquely positioned to contribute to the global efforts to prevent infant HIV infection and to optimize treatment of infected children. ADMINISTRATIVE COMPONENT: